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Item type:Publication, Access status: without files , Inline-Monitoring zur Prozesskettenverkürzung bei der spanenden Bearbeitung von CFK-FlugzeugstrukturenPublicationtype: Doctoral Thesis32 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Maschinelles Lernen zur Überwachung semi-automatischer Bohrprozesse im Flugzeugbau(2026); The large number of semi-automatically drilled holes in aircraft structural assembly provides a promising basis for the application of machine learning (ML) in data-based process monitoring using today's sensor technologies. This thesis investigates ML-based anomaly detection, process status, workpiece quality, and tool condition monitoring in semi-automatic drilling in order to identify the achievable prediction accuracies and optimal methods for the individual modeling steps.Publicationtype: Doctoral Thesis169 79 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , 57 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Efficient optimization of turning processes for powertrain components using multi model-based simulation(2026); In this thesis, various simulation methods for the analysis and optimization of turning processes in mass-scale production are developed and presented. The dry turning process was optimized by conducting simulations of different coating tools, coating thicknesses and tool cutting edge radii in commercial FEM software AdvantEdge. All simulations were experimentally validated. Two new simulation approaches were developed for flood lubricated turning process which significantly expanded the application of simulations. In the first approach, a coupling between two different software tools was developed and implemented. This solution coupled a commercial FEM tool (AdvantEdge) with a commercial CFD tool (Star-CCM+). In the second approach, a single software, LS-DYNA, was used to simulate flood lubricated orthogonal turning simulations. These simulations were additionally validated with literature and were compared to dry orthogonal turning simulations. Lastly, mechanistic modelling method was used in the MACHpro software to optimize the NC-program of inner contour turning process in mass production of turbine housing. For this purpose, a digital force model using FEM simulations was developed in order to optimize the NC program by means of feed-rate adjustments. By implementing these simulation results in mass-production, the tool life could be increased by 46%. Additionally, the best performing coating and coating thickness from the dry machining simulation was simulated with the mass production cutting insert geometry. In production tests, the optimized coating achieved a further increase of almost 75% in tool life and a reduction of 64% in the scrap costs.Publicationtype: Doctoral Thesis129 53 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Zerspankraftmodellierung und Prozessgrenzen der Umrissbearbeitung von FKV-Bauteilen mit scheibenförmigen Werkzeugen(2025); Machining of defined part contours is an essential step in the production of fiber-reinforced plastic (FRP) shell components. Besides milling, processes with disk-shaped tools such as abrasive cutting and sawing can be used for this purpose. In addition, Curved Circular Cutting (CCC) is a novel technology that enables the machining of curved contours with these type of tools. To date, however, there has been comparatively little research into these FRP machining processes. This results in a lack of suitable simulation models and detailed knowledge of the relevant technological process limits with regard to process design and optimization. This thesis addresses this need and provides a mechanistic cutting force model that can be used for cutting force simulations with arbitrary disk-shaped tool geometries. This model includes for the first time oblique cutting with spatial cutting phenomena at the fibers of the FRP, which can occur in the contact zone due to complex engagement conditions, especially when using the CCC technology. The resulting effect on the cutting behavior of the orthotropic material is systematically investigated by machining tests on unidirectional CFRP, mathematically modeled and integrated into the cutting force model. In addition, the results of comprehensive experimental investigations are used to identify the technological process limitations of CCC and to derive recommendations for the application.Publicationtype: Doctoral Thesis113 104 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , An intelligent versatile pipeline for 6D localization of industrial components in a production environmentPublicationtype: Doctoral Thesis30 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , 56 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Modellgestützte Berechnung der thermischen Belastung bei der Zerspanung von unidirektionalem CFK(2023); The primary challenges in milling of carbon fiber reinforced plastic (CFRP) workpieces are material and surface integrity as well as tool wear. Exacerbating these issues are high cutting zone temperatures which are inter alia difficult to assess due to steep temperature gradients. Furthermore, orientation of the fibers changes mechanical and thermal material properties. Instead of CFRP laminates consisting of differently oriented layers, this thesis focuses on the simplified case of unidirectional (UD) CFRP. Thus, thermal effects originating from the fiber orientation angle between tool path and fibers can be studied selectively. Modeling the heating of the workpiece as a moving strip-shaped heat source, an analytical formulation of the resulting temperature field for linear tool paths is developed and validated using experimental data. This model enables the development of a numerical simulation tool for straight tool paths which also allows to study nonlinear effects exceeding the scope of the analytical model. In addition, an experimentally validated simulation for convex tool paths with defined radii shows the influence of fiber orientation and radius on the heat accumulation in convex UD-CFRP workpiece sections.Publicationtype: Doctoral Thesis111 255 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Helixfräsen und Bohren von laseradditiv gefertigten Bauteilen aus Titan für LuftfahrtanwendungenBionically optimized components produced by selective laser melting (SLM) become established as aerospace components. For these components, support structures are essential for SLM in horizontal bores. To remove these support structures, helical milling and drilling processes are investigated in this work. By using the developed models, it is possible to identify the interaction between the cutting conditions, the machining forces, the chip formation and the quality of the inner wall of the bore.Publicationtype: Doctoral Thesis404 780 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Entwicklung eines hochgenauen Bearbeitungsroboters durch den Einsatz zusätzlicher MesstechnikThe rising demand for passenger aircrafts along with the modern concept of eco-efficient flying have resulted in several adaptive manufacturing strategies of large structure components especially made from composites. A flexible approach for machining is given by industrial robots, whose accuracy characteristics do not yet match the desired tolerances of the aerospace industry. This work investi-gates three different measuring systems that can be used to improve robot accuracy. A distinction is drawn between internal secondary encoder systems and external pose measuring systems, such as stereo camera systems or laser trackers. The results show significant improvements of the overall robot accuracy and offer a great potential for the machining of large components.Publicationtype: Doctoral Thesis826 4776